Wednesday, February 4, 2009

Tragic wind

The myth that windmills are an important part of the solution to our energy problem is a myth, and as a myth a cause of a tragic misunderstanding. Most people understand that wind is unreliable, but most people seem to believe that a solution to the problem of wind unreliability has either been found already, or will soon be found. Although various solutions to the wind reliability problem have been proposed, their practicality is uncertain, and their cost is far from clear. Viable wind reliability technologies are likely to be quite expensive. For example David Roberts once estimated that with 22 hours energy storage, base wind could be made reliable 99% of the time. Energy storage options would include underground compressed air storage, pump storage, and batteries. Let us assume for the moment that batteries are used to provide the storage. One GWh of Battery storage is estimated to run @$350,000,000. 22 hours of battery storage thus will cost as much as a reactor that produces 1 GW year of electricity every year. If you buy the reactor, not only is the battery not needed, but you can dispense with the windmills as well. Thus for the price of a battery backup system, you can have a far more flexible nuclear system. But if you buy the reliable nuclear system, you would have no reason to need the wind system at all.

Mark Z. Jacobson has argued that by combining the electrical output from windmills at 17 carefully selected locations in the Southern Great Plains, about 20% of the systems name tag output would be available 80% of the time. Jacobson suggests that wind generated electricity would be reliable as coal or nuclear as a base power source. There are several problems with Jacobson's wind peak generating system. The first is the cost of wind redundancy. While windmills at some of the 17 sites would be turning 80% of the time, there would be no wind blowing at other sites. Since the system can only be counted on to produce 20% of its name plate electricity, that means 5 watts of windmill power would have to be installed for every reliable watt of of electricity. That in turn means that 5 GWs of wind installation would count as the generation equivalent of a 1 GWe reactor. In order to supply reliable wind generated electricity a wind system would need to cost more than a nuclear sourced generating system, and battery back up top the wind system would nearly double the cost. Wind then would cost at least twice the cost of nuclear in order to equal nuclear in reliability.

The tragedy of wind is that the expectations are so great, but such expectations can only lead to great disapointment.

2 comments:

Warren Heath
said...

There’s an excellent summary of World Wind Turbine Installation costs, here . Average capital cost, documented in the report is $US 2586 per installed kw, with capital costs in Europe expected to rise to $US 4342 per peak kw in the next few years. With Germany & Denmark’s capacity factor at about 20% that works out to an incredible $21,710 per avg kw, not including the cost of the fossil fuel backup NG power plant, output smoothing battery bank and the quadruple or quintuple oversized, long distance power transmission system. Even at USA’s 25% average and $US 2586 per pk kw, that’s $US 10,344 per avg kw, plus $1000 per kw for backup power, plus $2000 per kw for the transmission line infrastructure, plus at least $500 per kw for grid stabilization battery banks (like Altairnano is selling), that’s about $US 13,000 per avg delivered kw. A mite pricey for unreliable, intermittent, environmentally destructive energy. Even the anti-nuclear critics can’t come up with prices that high for modern nuclear, which lasts for 60 years vs 20 years for the Wind Turbines.

The author lists about 1.5 US cents per kwh for maintenance costs – comparable to modern nuclear operating costs. Not included is royalties to landowners for transmission line right-of-ways and land usage.

And that NG backup power produces considerable CO2 emissions, as well as depleting precious NG fuel reserves. The modern, more reliable, Wind Turbines are also depleting our very limited supplies of rare-earth magnets which are vastly more useful economically and environmentally, when used for motors in E-Bikes, E-Scooters and Electric and Hybrid Electric Vehicles.

After about 20% of Grid Capacity, the United States would have no viable option but to use surplus Wind Energy to produce liquid fuels for energy storage, which will be at most 50% efficient, resulting in a doubling of the above costs.

Here’s is another excellent document on the Facts about Industrial Wind Energy . Note that Danish Wind Turbines, in actual fact, only supply less than 6% of Denmark’s electricity consumption, not the 20% commonly reported, as most of their Wind Energy is exported, displacing cleaner, greener hydro power in Norway.

Warren Heath wrote:... and the quadruple or quintuple oversized, long distance power transmission system.

I had forgotten about that aspect. We had an incident here in Washington State last year where it was windy at all the wind power sites, all at the same time. The folks at Bonneville Power Administration (who manage the transmission lines that the wind turbines feed into) were pulling their hair out. They were on the edge of power system instability with all the power being dumped into the system. With other forms of generation, they just request the power input be reduced, and it is done. However, by law they are forced to accept all the power the wind turbines put on the grid.